Re: gcj 3.0 post-mortem

[Richard Henderson <rth at redhat dot com>]

On Sun, Jul 08, 2001 at 12:16:44AM +0100, Joseph S. Myers wrote:
> So, you understand MD_FALLBACK_FRAME_STATE_FOR?  Would you like to
> document it in tm.texi, since the person who added it still hasn't done
> so despite previous requests and bug reports 

Sorry for being so delinquent.


r~



Index: tm.texi
===================================================================
RCS file: /cvs/gcc/egcs/gcc/doc/tm.texi,v
retrieving revision 1.25
diff -c -p -d -r1.25 tm.texi
*** tm.texi	2001/07/07 01:07:17	1.25
--- tm.texi	2001/07/08 07:04:33
*************** This describes the stack layout and call
*** 2496,2501 ****
--- 2496,2502 ----
  
  @menu
  * Frame Layout::
+ * Exception Handling::
  * Stack Checking::
  * Frame Registers::
  * Elimination::
*************** You only need to define this macro if th
*** 2680,2685 ****
--- 2681,2698 ----
  want to support call frame debugging information like that provided by
  DWARF 2.
  
+ @findex SMALL_STACK
+ @item SMALL_STACK
+ Define this macro if the stack size for the target is very small.  This
+ has the effect of disabling gcc's built-in @samp{alloca}, though
+ @samp{__builtin_alloca} is not affected.
+ @end table
+ 
+ @node Exception Handling
+ @subsection Exception Handling Support
+ @cindex exception handling
+ 
+ @table @code
  @findex EH_RETURN_DATA_REGNO
  @item EH_RETURN_DATA_REGNO (@var{N})
  A C expression whose value is the @var{N}th register number used for
*************** handled.  @var{encoding} is the format c
*** 2755,2765 ****
  of bytes that the format occupies, @var{addr} is the @code{SYMBOL_REF}
  to be emitted.
  
! @findex SMALL_STACK
! @item SMALL_STACK
! Define this macro if the stack size for the target is very small.  This
! has the effect of disabling gcc's built-in @samp{alloca}, though
! @samp{__builtin_alloca} is not affected.
  @end table
  
  @node Stack Checking
--- 2768,2788 ----
  of bytes that the format occupies, @var{addr} is the @code{SYMBOL_REF}
  to be emitted.
  
! @findex MD_FALLBACK_FRAME_STATE_FOR
! @item MD_FALLBACK_FRAME_STATE_FOR(@var{context}, @var{fs}, @var{success})
! This macro allows the target to add cpu and operating system specific
! code to the call-frame unwinder for use when there is no unwind data
! available.  The most common reason to implement this macro is to unwind
! through signal frames.
! 
! This macro is called from @code{uw_frame_state_for} in @file{unwind-dw2.c}
! and @file{unwind-ia64.c}.  @var{context} is an @code{_Unwind_Context};
! @var{fs} is an @code{_Unwind_FrameState}.  Examine @code{context->ra}
! for the address of the code being executed and @code{context->cfa} for
! the stack pointer value.  If the frame can be decoded, the register save
! addresses should be updated in @var{fs} and the macro should branch to
! @var{success}.  If the frame cannot be decoded, the macro should do 
! nothing.
  @end table
  
  @node Stack Checking